Monitors for agricultural equipment which have the capability to record and store multiple levels of measured data have existed for some time. An example of such a monitor is the Acu-Grain GMS-3, which can store three levels of totals: Load, Field and Total. These levels represent the mount of grain measured from the most recently harvested Load, the mount of grain accumulated in the: most recently harvested Field, and the total amount of grain accumulated since the Total counter has been cleared. The Field value may be the sum of several Load values and the Total value may be the sum of several Field values.
However, a disadvantage of this type of data storage system is that only one value for each level can be stored. When it is desired to record a new Load, Field or Total value, the previous value must be cleared from the monitor, and is lost unless it is recorded with other means, such as manually writing it in a notebook.
Systems for recording large mounts of data, such as from many crop variety test plots, have utilized portable computers with a keyboard or pointing device for operation of the computer. However, the numerous operator actions required to operate a computer are undesirable when operating agricultural machinery, since the operator is already performing many other operational tasks.
Whatever the precise merits, features and advantages of these types of data storage methods and devices, it will be seen that none of them provides all of the objects of the present invention.